1. Field of the Invention
Methods and apparatuses consistent with the exemplary embodiments relate to a down-converter, up-converter, receiver and transmitter applying the same, and more particularly, to a down-converter and up-converter using a plurality of mixers, and a receiver and transmitter applying the same.
2. Background Art
In a 60 GHz RF (Radio Frequency) system for high speed data transmission, the method of generating LO (Local Oscillator) signals for frequency conversion is very difficult.
Especially, it is necessary to generate a swing full enough to switch a mixer, and to generate a high frequency of 60 GHz. In a case of making a transceiver with a direct conversion type frequency conversion circuit, generating signals of 60 GHz consumes a lot of power and is highly sensitivity to parasitic, making it difficult to adjust the LC resonance. Furthermore, using a double conversion type frequency conversion circuit requires various LOs, and thus it becomes necessary to generate a VCO (Voltage Controlled Oscillator) frequency of a common high frequency, or make various VCOs.
As such, each of the two types of conventional frequency converters has its advantages, but they also have disadvantages. Thus, there is a need to seek a method for providing a frequency converter which overcomes the above disadvantages of those two types of conventional frequency converters.